By Dr. Lisa Wang — Not a real doctor. Just someone who stretched for years before running. Then learned she was doing it wrong.
Last updated: June 2026
You have been told to stretch before exercise. Touch your toes. Hold for 30 seconds. Feel the burn. Prevent injury.
This advice is everywhere. It is also mostly wrong.
Not all stretching is bad. But the type most people do, at the time most people do it, does not do what you think it does.
Static vs. Dynamic Stretching
There are two main types of stretching.
| Type | What It Is | Example |
|---|---|---|
| Static | Hold a stretch in one position | Touching your toes and holding for 30 seconds |
| Dynamic | Moving through a range of motion | Leg swings, arm circles, walking lunges |
Static stretching is what most people think of as stretching. Dynamic stretching is what you should do before exercise.
What the Research Says
Static stretching before exercise does not prevent injury.
Multiple large studies have found no reduction in injury rates from pre-exercise static stretching. It does not protect your muscles.
Static stretching before exercise reduces performance.
Holding a stretch for 30-60 seconds temporarily reduces muscle strength and power. Your muscles are slightly weaker for up to an hour after static stretching.
| Effect | Reduction |
|---|---|
| Muscle strength | 3-8% |
| Power output | 2-5% |
| Jump height | 2-4% |
| Sprint speed | 1-3% |
These numbers are not huge. But they matter if you are competing or trying to improve.
Dynamic stretching before exercise improves performance.
Moving your muscles through a range of motion warms them up. It increases blood flow. It activates the nervous system. Dynamic stretching prepares your body for activity.
What to Do Before Exercise
Warm up first.
A proper warm-up raises your body temperature. Light cardio for 5-10 minutes. Jogging, jumping jacks, cycling.
Then do dynamic stretches.
| Exercise | Dynamic Stretch |
|---|---|
| Running | Leg swings, walking lunges, high knees, butt kicks |
| Weightlifting | Arm circles, torso twists, bodyweight squats, cat-cow |
| Soccer/basketball | Side lunges, high knees, carioca (grapevine) |
| Swimming | Arm circles, torso twists, shoulder rotations |
Dynamic stretches should feel active, not passive. You should be moving continuously.
What to Do After Exercise
Static stretching after exercise is fine.
After your workout, when your muscles are warm, static stretching can improve flexibility and aid recovery.
Hold each stretch for 15-30 seconds.
Do not bounce. Do not push to pain. Feel a gentle stretch.
| Muscle | Stretch |
|---|---|
| Hamstrings | Seated forward fold or lying hamstring stretch |
| Quadriceps | Standing quad pull (pull heel toward glute) |
| Chest | Doorway stretch |
| Lower back | Knees to chest |
| Calves | Downward dog or calf stretch against a wall |
When Static Stretching Makes Sense
| Situation | Static Stretching Helps |
|---|---|
| After exercise | Yes. Muscles are warm. |
| On rest days | Yes. Improves flexibility. |
| Before bed | Yes. Relaxes the body. |
| For sports requiring extreme flexibility | Yes. Gymnastics, dance, martial arts. |
| Before exercise (most people) | No. Do dynamic instead. |
Common Myths
Myth: Stretching prevents injury.
For static stretching before exercise, false. For dynamic stretching, possibly true. For overall flexibility, weak evidence.
Myth: You need to stretch tight muscles.
Tight muscles may be weak, not short. Strengthening is often more effective than stretching.
Myth: No pain, no gain.
Pain is not the goal. Stretch to a point of gentle tension. Pain means you are overdoing it.
Myth: Stretching before exercise warms you up.
Stretching does not raise body temperature. Light cardio does. Warm up first, then stretch.
A Better Pre-Exercise Routine
| Step | Time | Activity |
|---|---|---|
| 1 | 5 minutes | Light cardio (jog, jump jacks, bike) |
| 2 | 5 minutes | Dynamic stretches (leg swings, lunges, arm circles) |
| 3 | Your workout | |
| 4 | 5-10 minutes | Static stretches (after workout) |
This routine takes 10-15 minutes before exercise. It prepares your body better than 10 minutes of static stretching.
What to Do If You Have Limited Time
If you only have 5 minutes before a workout, do dynamic stretches. Skip the light cardio. Skip the static stretching.
Dynamic stretching is more valuable than static stretching before exercise.
The Bottom Line
Static stretching before exercise does not prevent injury. It may reduce your performance.
Dynamic stretching before exercise warms up your muscles and improves performance.
Save static stretching for after your workout, on rest days, or before bed.
Warm up. Move dynamically. Work out. Stretch statically afterward.
Your body will thank you.
About the author: Lisa Wang stretched before every run for years. She stopped. She runs better now.
This article is for informational purposes. Different bodies have different needs. If you have a specific injury or condition, consult a physical therapist.